# CVE-2026-26928: Lack of Dynamic Library Validation in SzafirHost

> Attackers can execute arbitrary code by providing malicious dynamic libraries that bypass signature verification in SzafirHost.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 2 Apr 2026
- **Updated:** 2 Apr 2026
- **Also known as:** GHSA-cg6j-gw4m-cw76

## What is CVE-2026-26928?

CVE-2026-26928 is a high-severity code injection vulnerability in Krajowa Izba Rozliczeniowa SzafirHost, published on 2 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

SzafirHost downloads necessary files in the context of the initiating web page. When called, SzafirHost updates its dynamic library. JAR files are correctly verified based on a list of trusted file hashes, and if a file was not on that list, it was checked to see if it had been digitally signed by the vendor. The application doesn't verify hash or vendor's digital signature of uploaded DLL, SO, JNILIB or DYLIB file. The attacker can provide malicious file which will be saved in users /temp folder and executed by the application.

This issue was fixed in version 1.1.0.

Weakness: CWE-354 (Improper Validation of Integrity Check Value)

## Which versions are affected by CVE-2026-26928?


## How do I fix CVE-2026-26928?

No fix has been published for CVE-2026-26928 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-26928 being exploited?

There is no known exploitation of CVE-2026-26928 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-26928 and fix it if it is affected.

What it is: CVE-2026-26928 is a high-severity code injection vulnerability in Krajowa Izba Rozliczeniowa SzafirHost, published on 2 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-26928 in the wild and no public exploit code.

Affected product: Krajowa Izba Rozliczeniowa SzafirHost. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-26928/ (Markdown: https://insights.sbomify.com/CVE-2026-26928/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-26928
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-26928
- OSV: https://osv.dev/vulnerability/CVE-2026-26928

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-26928/
Summaries are generated and may contain mistakes; the official description above is the record.